Abstract: In a control device mounted on a vehicle provided with a traction motor, and including a processing unit and a storage unit, the processing unit sets a stored value stored in the storage unit to a predetermined parameter related to the drive control of the motor when reaching the first predetermined timing, and executes the estimation processing for this time for the estimated value related to the predetermined parameter using the stored value as an initial value, and when reaching the second predetermined timing, stores the estimated value in the estimation processing for this time as a stored value in the storage unit.

Abstract: A drive device corrects a d-axis detection current and a q-axis detection current such that a d-axis voltage error between a d-axis estimated voltage based on the torque command and a magnet temperature of the permanent magnet of a motor and a d-axis detection voltage based on the d-axis detection current or a q-axis magnetic flux error between a q-axis estimated magnetic flux based on the torque command and the magnet temperature and a q-axis detection magnetic flux based on the q-axis detection current is a value zero, calculates a d-axis current after the correction and a q-axis current after the correction, and controls the inverter such that a difference between values of the d-axis current after the correction and the q-axis current after the correction and the values of the d-axis current command and the q-axis current command is cancelled out.

Abstract: A control system for an electric vehicle configured to control output torques of each motor independently so as to improve a running stability and a control stability. Each of the motors is connected individually to one of wheels so that drive forces established by the wheels are controlled independently by controlling output torques of motors independently. A control unit is configured to: calculate estimated parameters of the motors; select a reference motor; calculate a difference between the estimated parameters of the reference motor and other motor; and control the torques of the motors to reduce a difference between the torques of the reference motor and other motor.

Abstract: An absolute encoder has a code plate formed with an absolute pattern and an incremental pattern. A first detector detects the absolute pattern, and outputs an absolute signal. A second detector detects the incremental pattern, and outputs an incremental signal. The absolute encoder stores the absolute signal according to an external input signal, and forms a corrected absolute signal on the basis of the incremental signal input after the absolute signal is stored.

Abstract: An absolute encoder device comprises a code plate having a 1-track type absolute pattern whose minimum reading unit length is .lambda., a first incremental pattern with a pitch .lambda., and a second incremental pattern with pitch 2.sup.-n .lambda.. The device also comprises a detector section, which is movable relative to the code plate, which includes a detector detecting the absolute pattern and obtaining an absolute pattern signal, a detector detecting a first incremental pattern and obtaining a first incremental signal, and a detector detecting a second incremental pattern and obtaining a second incremental pattern signal. A shorter cyclic incremental signal is generated from the first incremental signal by interpolating and the shorter cyclic signal is synchronized with the second incremental signal. The absolute pattern signal, the second incremental signal and the synchronized first incremental signal represent the relative positional relationship between the code plate and the detector section.